Restoration of Natural Drainage Courses and Mitigation of Soil Erosion at a High Severity Burn in the Fraser Plateau of British Columbia
AbstractThe 2017 Canim Lake Fire, labelled C41703 by the British Columbia (BC) Wildfire Service, ignited by lightning strike on August 12, 2017. The fire burned an estimated 195 ha of forested land and was considered to be an interface fire due to its proximity to lakeshore private properties on Canim Lake (BC Wildfire Service, Sep. 6, 2017). Approximately 14,671 m of fire guard were constructed to contain and suppress the fire. A fire rehabilitation plan was created that included measures for decking and removal of fallen timber, restoring natural drainages, grass seeding fire guards to mitigate soil erosion and the establishment of invasive species, and stabilizing sumps and dams. Given that the Canim Lake Fire C41703 is considered to be an interface fire, the restoration goal for this project is to restore the natural drainage patterns and mitigate downstream impacts due to erosion, including the potential for mass wasting events such as landslides or debris flows. The plan was implemented in November 2017. Based on initial monitoring of the site, the restoration of natural drainage patterns within the fire control works appears to have been successful at managing the flow of water during the 2018 spring freshet. In addition, substantial new plant growth was observed on the restored fire guards and much of the area burned by the fire. However, in some areas burned by the fire new plant growth was patchy, which may be because of hydrophobic soils and may require more time before plants establish. One staging area was not rehabilitated as it was identified during the initial site assessments as being useful in a potential future salvage logging operation. Recommendations for potential salvage logging and future site monitoring are also discussed in this report.